Display device

ABSTRACT

According to an aspect, a display device includes a display panel provided with a display region including a plurality of pixels and with a plurality of detection electrodes. The display panel includes: a plurality of lines of first common wiring configured to transmit pixel signals to be supplied to the pixels and a detection input/output signal to be supplied to the detection electrodes; pixel signal wiring electrically coupled to the pixels; detection electrode wiring electrically coupled to the detection electrodes; a first switching circuit configured to electrically couple or uncouple the first common wiring to or from the pixel signal wiring; and a second switching circuit configured to electrically couple or uncouple the first common wiring to or from the detection electrode wiring.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a bypass continuation of PCT filingPCT/JP2019/016902, filed Apr. 19, 2019, which claims the benefit ofpriority from Japanese Patent Application No. 2018-081657, filed Apr.20, 2018, the entire contents of each are incorporated herein byreference.

BACKGROUND 1. Technical Field

What is disclosed herein relates to a display device.

2. Description of the Related Art

In recent years, as a display device such as a liquid crystal displaydevice used in, for example, a personal digital assistant (PDA), what iscalled a display device with a touch detection function provided with adetection device capable of detecting an external proximate object hasbeen widely used. Such a display device with a touch detection functiontypically has a configuration in which the detection device is mountedon or integrated with a display region of a display panel.

There are capacitive detection devices that detect a position of theexternal proximate object using a change in electrostatic capacitancegenerated on a plurality of detection electrodes provided on a detectionsurface. In the display device with a touch detection function usingsuch a capacitive detection device, increasing the detection electrodesto improve detection accuracy leads to increase in number of lines ofwiring for supplying drive signals for detection to the detectionelectrodes, which in turn leads to a complicated wiring layout on thedisplay panel. If a configuration is employed in which a drive circuitfor performing display operation and a detection circuit for performingthe detection operation are integrated into a semiconductor chip such asa driver integrated circuit (IC), the number of terminals of thesemiconductor chip increases, so that the semiconductor chip mayincrease in size. The increase in the number of lines of the wiringcoupled to the display panel may also lead to an increase in width of acoupling portion between a circuit board for mounting the driver IC andthe display panel. For example, a technology has been disclosed thatuses a shift register and a multiplexer to reduce the number of lines ofthe wiring for supplying the drive signals for detection.

In the above-described conventional technology, since the shift registerneeds to be provided on the display panel, a peripheral region outsidethe display region of the display panel may increase in width. As thenumber of lines of the wiring for supplying the drive signals fordetection is reduced, the circuit scale of the shift register and themultiplexer increases, so that the peripheral region of the displaypanel may be occupied by a larger circuit area.

For the foregoing reasons, there is a need for a display device capableof reducing the number of lines of the wiring coupled to the displaypanel.

SUMMARY

According to an aspect, a display device includes a display panelprovided with a display region including a plurality of pixels and witha plurality of detection electrodes. The display panel includes: aplurality of lines of first common wiring configured to transmit pixelsignals to be supplied to the pixels and a detection input/output signalto be supplied to the detection electrodes; pixel signal wiringelectrically coupled to the pixels; detection electrode wiringelectrically coupled to the detection electrodes; a first switchingcircuit configured to electrically couple or uncouple the first commonwiring to or from the pixel signal wiring; and a second switchingcircuit configured to electrically couple or uncouple the first commonwiring to or from the detection electrode wiring.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a configuration example of adisplay device according to a first embodiment;

FIG. 2 is a block diagram illustrating a configuration example of adetection circuit;

FIG. 3 is an explanatory diagram for explaining the basic principle ofself-capacitive detection, which illustrates a state where a detectiontarget object is present;

FIG. 4 is a diagram illustrating an example of waveforms of a drivesignal and a detection signal of the self-capacitive detection;

FIG. 5 is a sectional view illustrating a schematic sectional structureof the display device according to the first embodiment;

FIG. 6 is a plan view schematically illustrating an array substrate;

FIG. 7 is a circuit diagram illustrating a pixel array of a displayregion according to the first embodiment;

FIG. 8 is a perspective view illustrating an arrangement example ofdetection electrodes;

FIG. 9 is a diagram illustrating a time division example between adisplay mode and a detection mode in the display device according to thefirst embodiment;

FIG. 10A is an explanatory diagram for explaining a state where thedetection electrodes supplied with detection input/output signals aresequentially selected and switched;

FIG. 10B is an explanatory diagram for explaining another state wherethe detection electrodes supplied with the detection input/outputsignals are sequentially selected and switched;

FIG. 10C is an explanatory diagram for explaining still another statewhere the detection electrodes supplied with the detection input/outputsignals are sequentially selected and switched;

FIG. 10D is an explanatory diagram for explaining still another statewhere the detection electrodes supplied with the detection input/outputsignals are sequentially selected and switched;

FIG. 11 is a diagram illustrating an example of detection periods duringwhich the detection input/output signals are supplied to the respectivedetection electrodes;

FIG. 12 is a block diagram illustrating a configuration example of adisplay device according to a first comparative example with respect tothe first embodiment;

FIG. 13 is a diagram illustrating a configuration of an output circuitand a coupling circuit of the display device according to the firstcomparative example with respect to the first embodiment;

FIG. 14 is a diagram illustrating a timing control example of thedisplay device according to the first comparative example with respectto the first embodiment;

FIG. 15 is a block diagram illustrating a configuration example of adisplay device according to a second comparative example with respect tothe first embodiment;

FIG. 16 is a diagram illustrating a configuration of an output circuitand a coupling circuit of the display device according to the secondcomparative example with respect to the first embodiment;

FIG. 17 is a diagram illustrating a timing control example of thedisplay device according to the second comparative example with respectto the first embodiment;

FIG. 18 is a diagram illustrating a configuration of an output circuitand a coupling circuit of the display device according to the firstembodiment;

FIG. 19 is a diagram illustrating a timing control example of thedisplay device according to the first embodiment;

FIG. 20 is a block diagram illustrating a configuration example of adisplay device according to a modification of the first embodiment;

FIG. 21 is a diagram illustrating a configuration of the output circuitand a coupling circuit of the display device according to themodification of the first embodiment;

FIG. 22 is a diagram illustrating a timing control example of thedisplay device according to the modification of the first embodiment;

FIG. 23 is a block diagram illustrating a configuration example of adisplay device according to a second embodiment;

FIG. 24 is a diagram illustrating a configuration of an output circuitand a coupling circuit of the display device according to the secondembodiment;

FIG. 25 is a diagram illustrating a timing control example of thedisplay device according to the second embodiment;

FIG. 26 is a block diagram illustrating a configuration example of adisplay device according to a third embodiment;

FIG. 27 is a diagram illustrating a configuration of an output circuitand the coupling circuit of the display device according to the thirdembodiment; and

FIG. 28 is a diagram illustrating a timing control example of thedisplay device according to the third embodiment.

DETAILED DESCRIPTION

The following describes modes (embodiments) for carrying out the presentdisclosure in detail with reference to the drawings. The presentdisclosure is not limited to the description of the embodiments givenbelow. Components described below include those easily conceivable bythose skilled in the art or those substantially identical thereto.Furthermore, the components described below can be combined asappropriate. The disclosure is merely an example, and the presentdisclosure naturally encompasses appropriate modifications easilyconceivable by those skilled in the art while maintaining the gist ofthe disclosure. To further clarify the description, widths, thicknesses,shapes, and the like of various parts may be schematically illustratedin the drawings as compared with actual aspects thereof. However, theyare merely examples, and the interpretation of the present disclosure isnot limited thereto. The same component as that described with referenceto an already mentioned drawing is denoted by the same reference numeralthrough the description and the drawings, and detailed descriptionthereof may not be repeated where appropriate.

In this disclosure, when an element is described as being “on” anotherelement, the element can be directly on the other element, or there canbe one or more elements between the element and the other element.

First Embodiment

FIG. 1 is a block diagram illustrating a configuration example of adisplay device according to a first embodiment. FIG. 2 is a blockdiagram illustrating a configuration example of a detection circuit. Asillustrated in FIG. 1, a display device 1 includes a display panel 10, acontrol circuit 11, a detection circuit 40, an analog front end 17, andan output circuit 100. The control circuit 11, the detection circuit 40,the analog front end 17, and the output circuit 100 are included in adrive circuit 19. The drive circuit 19 is what is called a driver IC,and drives the display panel 10. The drive circuit 19 is the driver ICincluding, for example, an integrated circuit.

The display panel 10 includes a display region 20 for displaying animage and a sensing region 30 included in a detection device fordetecting a touch input. The block diagrams illustrated in FIGS. 1 and 2are diagrams for conceptually explaining the configurations, which maybe other configurations.

The display panel 10 is a display device in which the display region 20is integrated with the sensing region 30. Specifically, in the displaypanel 10, some of the members of the display region 20, including, forexample, electrodes and substrates are also used as, for example,electrodes and substrates of the sensing region 30.

Liquid crystal display elements are used as display elements of thedisplay region 20. The display region 20 includes a plurality of pixelshaving the display elements, and has a display surface facing thepixels. The display region 20 receives an input of a video signal Vdisp,and displays the image formed of pixels on the display surface. Thedisplay region 20 may be, for example, an organic electroluminescent(EL) display panel.

The display panel 10 further includes a coupling circuit 200. Thecoupling circuit 200 is provided in a peripheral region 18 outside thedisplay region 20 of the display panel 10. The coupling circuit 200 is acircuit that switches between coupling and uncoupling the drive circuit19 and the lines of wiring in the display region 20 based on, forexample, a control signal supplied from the control circuit 11. Thedisplay panel 10 also includes a gate scanner circuit 12 to be describedlater.

The control circuit 11 includes a source driver 13 and a drive electrodedriver 14. The control circuit 11 is a circuit that controls displayoperation and detection operation based on the externally supplied videosignal Vdisp.

The control circuit 11 supplies a scan signal Vscan through the gatescanner circuit 12 to each horizontal line serving as a target ofdisplay driving of the display panel 10. This operation sequentially orsimultaneously selects each horizontal line as the target of displaydriving.

The source driver 13 is a circuit that generates a pixel signal Vpix tobe supplied to each pixel Pix of the display region 20 (refer to FIG.7). The polarity of the pixel signal Vpix may be inverted for eachframe, for each horizontal period, or for each column of the videosignal Vdisp.

The drive electrode driver 14 is a circuit that generates a displaydrive signal VCOM to be supplied to a detection electrode DE of thedisplay panel 10 (refer to FIGS. 5 and 6). The drive electrode driver 14generates a detection drive signal Vself to be supplied to the detectionelectrode DE serving as a common electrode of the display panel 10. Thedrive electrode driver 14 has a function to generate a guard signal Vgdthat has the same waveform as that of the detection drive signal Vselfand is synchronized with the detection drive signal Vself.

In the present embodiment, the display device 1 has a display mode ofperforming the display using the display region 20 and a detection modeof detecting a detection target object (hereinafter, also called “touchdetection”) in the sensing region 30, as operation modes. The controlcircuit 11 performs the display mode operation and the detection modeoperation in a time-division manner. In the present disclosure, the term“touch detection” refers to detecting a position of the detection targetobject in a state where the detection target object is in contact with adetection surface or the display surface, or in a state where thedetection target object is proximate to the detection surface or thedisplay surface enough to became equated with being in contacttherewith. The control circuit 11 may have a hover detection mode as adetection mode in addition to the touch detection mode. In this case,the term “hover detection” refers to detecting the position and amovement of the detection target object in a state where the detectiontarget object is not in contact with the detection surface or thedisplay surface, or in a state where the detection target object is notproximate to the detection surface or the display surface enough tobecame equated with being in contact therewith.

A touch sensor of the sensing region 30 includes a function to detectthe position of the detection target object in contact with or proximateto the detection surface or the display surface of the display panel 10based on the basic principle of detection of the detection target objectusing a self-capacitance method to be described later.

The detection circuit 40 is a circuit that detects the detection targetobject in proximity to the display surface of the display panel 10serving as the detection surface in the self-capacitive touch detection.If the detection surface is touched, the detection circuit 40 obtains,for example, coordinates where the touch input is made.

As illustrated in FIG. 2, the detection circuit 40 includes ananalog-to-digital (A/D) conversion circuit 43, a signal processingcircuit 44, a coordinate extraction circuit 45, and a detection timingcontrol circuit 46. Based on a control signal supplied from the driveelectrode driver 14, the detection timing control circuit 46 controlsthe A/D conversion circuit 43, the signal processing circuit 44, and thecoordinate extraction circuit 45 so as to operate them insynchronization with one another.

The drive electrode driver 14 supplies the detection drive signal Vselfthrough the analog front end 17 to the detection electrode DE to bedescribed later. The detection circuit 40 receives a detection signalVdet supplied from the detection electrode DE through the analog frontend 17. The analog front end 17 performs signal regulation on thedetection signal Vdet by, for example, reducing the noise thereof andamplifying the signal component thereof. A signal between the analogfront end 17 and the detection electrode DE is hereinafter called a“detection input/output signal AFE”.

The A/D conversion circuit 43 samples the analog signals output from theanalog front end 17 and converts them into digital signals at timessynchronized with the detection drive signal Vself.

The signal processing circuit 44 is a logic circuit that detects whetherthe display panel 10 is touched based on output signals of the A/Dconversion circuit 43. The signal processing circuit 44 performsprocessing of extracting a signal of a difference in detection signal(absolute value |ΔV|) caused by a finger. The signal processing circuit44 compares the absolute value |ΔV| with a predetermined thresholdvoltage, and, if the absolute value |ΔV| is below the threshold voltage,determines that the detection target object is in an absent state. If,instead, the absolute value |ΔV| is equal to or above the thresholdvoltage, the signal processing circuit 44 determines that the detectiontarget object is in a present state. In this way, the detection circuit40 can perform the touch detection.

The coordinate extraction circuit 45 is a logic circuit that obtains thecoordinates of the detection target object when the detection targetobject is detected by the signal processing circuit 44. The coordinateextraction circuit 45 outputs the coordinates of the detection targetobject as an output signal Vout. The coordinate extraction circuit 45may output the output signal Vout to the control circuit 11. The controlcircuit 11 can perform a predetermined display operation or detectionoperation based on the output signal Vout.

The A/D conversion circuit 43, the signal processing circuit 44, thecoordinate extraction circuit 45, and the detection timing controlcircuit 46 of the detection circuit 40 are incorporated in the displaydevice 1. The present disclosure is, however, not limited to thisconfiguration. All or some of the functions of the detection circuit 40may be incorporated in an external processor or the like. For example,the coordinate extraction circuit 45 may be incorporated in the externalprocessor separate from the display device 1, and the detection circuit40 may output the signal processed by the signal processing circuit 44as the output signal Vout.

The pixel signal Vpix, the display drive signal VCOM, the guard signalVgd, and the detection input/output signal AFE are switched in atime-division manner by the output circuit 100 and the coupling circuit200, and are supplied to the display region 20 and the sensing region30. Detailed configurations and operations of the output circuit 100 andthe coupling circuit 200 will be described later.

The display panel 10 is subjected to touch control based on the basicprinciple of the capacitive touch detection. The following describes thebasic principle of detection of the detection target object using theself-capacitance method performed on the display panel 10 of the presentembodiment, with reference to FIGS. 3 and 4. FIG. 3 is an explanatorydiagram for explaining the basic principle of the self-capacitivedetection, illustrating the state where the detection target object ispresent. FIG. 4 is a diagram illustrating an example of waveforms of thedrive signal and the detection signal of the self-capacitive detection.FIG. 3 illustrates also a detection circuit. Although the followingdescribes the case where the detection target object is a finger, thedetection target object is not limited to a finger, and may be an objectincluding a conductor, such as a stylus pen.

When the detection target object is in the absent state, an alternatingcurrent (AC) rectangular wave Sg having a predetermined frequency(ranging, for example, roughly from several kilohertz to several hundredkilohertz) is applied to a detection electrode E1. The detectionelectrode E1 has electrostatic capacitance C1, and a currentcorresponding to the electrostatic capacitance C1 flows. A voltagedetector DET converts a variation in the current corresponding to the ACrectangular wave Sg into a variation in voltage (waveform V₀ indicatedby a solid line, refer to FIG. 4).

Then, as illustrated in FIG. 3, when the detection target object is inthe present state, electrostatic capacitance C2 between the finger andthe detection electrode E1 is added to the electrostatic capacitance C1of the detection electrode E1. Consequently, a current corresponding tothe electrostatic capacitance C1 and the electrostatic capacitance C2flows when the AC rectangular wave Sg is applied to the detectionelectrode E1. As illustrated in FIG. 4, the voltage detector DETconverts the variation in the current corresponding to the ACrectangular wave Sg into a variation in voltage (waveform V₁ indicatedby a dotted line). The presence of the detection target object isdetected based on the absolute value |ΔV| of the difference between thewaveform V₀ and the waveform V₁.

Specifically, in FIG. 4, the AC rectangular wave Sg rises to a levelcorresponding to a voltage V₂ at time T₀₁. At this time, a switch SW1 isturned on and a switch SW2 is turned off, so that the potential of thedetection electrode E1 also rises to the voltage V₂. Then, the switchSW1 is turned off before time T₁₁. At this time, the detection electrodeE1 is brought into a floating state, but the potential of the detectionelectrode E1 is maintained at V₂ by the electrostatic capacitance C1 (orC1+C2, refer to FIG. 3) of the detection electrode E1. In addition, thevoltage detector DET is reset before time T₁₁.

Subsequently, turning on the switch SW2 at time T₁₁ moves an electriccharge stored in the electrostatic capacitance C1 (or C1+C2) of thedetection electrode E1 to a capacitor C3 in the voltage detector DET. Asa result, the output of the voltage detector DET increases (refer to thedetection signal Vdet in FIG. 4). When the detection target object is inthe absent state, the output (detection signal Vdet) of the voltagedetector DET forms the waveform V₀ indicated by the solid line, and isgiven as Vdet=C1×V₂/C3. When the detection target object is in thepresent state, the output (detection signal Vdet) forms the waveform V₁indicated by the dotted line, and is given as Vdet=(C1+C2)×V₂/C3.

Then, at time T₃₁, the switch SW2 is turned off and the switch SW1 and aswitch SW3 is turned on. As a result, the potential of the detectionelectrode E1 is set to a low level equal to the potential of the ACrectangular wave Sg, and the voltage detector DET is reset. Theoperation described above is repeated at the predetermined frequency(ranging, for example, roughly from several kilohertz to several hundredkilohertz). In this way, the detection circuit 40 can detect the presentstate of the detection target object based on the basic principle ofdetection of the detection target object using the self-capacitancemethod.

The following describes a configuration example of the display device 1in detail. FIG. 5 is a sectional view illustrating a schematic sectionalstructure of the display device according to the first embodiment. Asillustrated in FIG. 5, the display panel 10 includes an array substrate2, a counter substrate 3, and a liquid crystal layer 6 as a displayfunctional layer. The counter substrate 3 is disposed so as to face asurface of the array substrate 2 in a direction orthogonal thereto. Theliquid crystal layer 6 is provided between the array substrate 2 and thecounter substrate 3.

The array substrate 2 includes a first substrate 21, a pixel electrode22, the detection electrode DE, an insulating layer 24, and a polarizingplate 35B. The first substrate 21 is provided with circuits including,for example, the gate scanner circuit 12, switching elements such asthin-film transistors (TFTs), and various types of wiring including gatelines GCL and signal lines SGL (not fully illustrated in FIG. 7).

The detection electrode DE is provided on an upper side of the firstsubstrate 21. The pixel electrode 22 is provided on the upper side ofthe detection electrode DE with the insulating layer 24 interposedtherebetween, and a plurality of the pixel electrodes 22 are arranged ina matrix having a row-column configuration in a plan view. The pixelelectrode 22 is provided so as to correspond to a sub-pixel SPixincluded in each of the pixels Pix (refer to FIG. 7) of the displaypanel 10, and is supplied with the pixel signal Vpix for performing thedisplay operation. The detection electrode DE is supplied with thedisplay drive signal VCOM during the display operation, and serves asthe common electrode for the pixel electrodes 22. The polarizing plate35B is provided on a lower side of the first substrate 21.

In the present embodiment, for example, a light-transmitting conductivematerial such as indium tin oxide (ITO) is used for the pixel electrode22 and the detection electrode DE.

In the present specification, the term “upper side” denotes a directionfrom the first substrate 21 toward a second substrate 31 in a directionorthogonal to the first substrate 21. The term “lower side” denotes adirection from the second substrate 31 toward the first substrate 21.

The arrangement of the pixel electrodes 22 can not only be the matrixarrangement in which the pixel electrodes 22 are arranged in a firstdirection Dx and a second direction Dy orthogonal to the first directionDx, but also employ a configuration in which the pixel electrodes 22facing each other are arranged so as to be displaced from each other inthe first direction Dx or the second direction Dy. A configuration canalso be employed in which, using a difference in size between the pixelelectrodes 22 facing each other, two or three of the pixel electrodes 22are arranged on one side of one of the pixel electrodes 22 included in apixel array arranged in the first direction Dx.

The counter substrate 3 includes the second substrate 31, a color filter32 formed on one surface of the second substrate 31, and a polarizingplate 35A provided on the other surface of the second substrate 31. Thecolor filter 32 faces the liquid crystal layer 6 in the directionorthogonal to the first substrate 21. The color filter 32 may bedisposed on the first substrate 21. In the present embodiment, the firstsubstrate 21 and the second substrate 31 are, for example, glasssubstrates or resin substrates.

The first substrate 21 and the second substrate 31 are arranged so as toface each other with a predetermined gap provided therebetween. Theliquid crystal layer 6 is provided between the first substrate 21 andthe second substrate 31. In the liquid crystal layer 6, the orientationstate of liquid crystal molecules changes corresponding to a state of anelectric field generated between layers. As a result, transmitted lightis modulated. For example, a horizontal electric field mode, such as anin-plane switching (IPS) mode including a fringe field switching (FFS)mode is employed as an electric field mode for such a modulation.Orientation films (not illustrated in FIG. 5) for setting an initialorientation state of the liquid crystal molecules are formed on theoutermost surface of the array substrate 2 and the outermost surface ofthe counter substrate 3, the substrates 2 and 3 facing the liquidcrystal layer 6 illustrated in FIG. 5.

An illumination unit (backlight), which is not illustrated, is providedon the lower side of the first substrate 21. The illumination unitincludes a light source such as a light-emitting diode (LED), and emitslight from the light source toward the first substrate 21. The lightfrom the illumination unit passes through the array substrate 2, and ismodulated according to the orientation state of the liquid crystal at alocation of the light. Thus, the state of transmission of the light tothe display surface varies with location. As a result, the image isdisplayed on the display surface.

FIG. 6 is a plan view schematically illustrating the array substrate. Asillustrated in FIG. 6, in the display device 1, the peripheral region 18is provided outside the display region 20. In the present disclosure,the display region 20 is a region for displaying the image, and is aregion overlapping the pixels Pix (sub-pixels SPix). The peripheralregion 18 refers to a region inside the outer circumference of the firstsubstrate 21 and outside the display region 20. The peripheral region 18may have a frame-like shape surrounding the display region 20. In thatcase, the peripheral region 18 can be called a frame region.

In the present embodiment, the first direction Dx is a direction along ashort side of the display region 20. The second direction Dy is adirection orthogonal to the first direction Dx. The second direction Dyis not limited to this direction, and may intersect the first directionDx at an angle other than 90 degrees. A plane defined by the firstdirection Dx and the second direction Dy is parallel to a surface of thefirst substrate 21. A third direction Dz intersecting the firstdirection Dx and the second direction Dy is a thickness direction of thefirst substrate 21.

As illustrated in FIG. 6, a plurality of the detection electrodes DE arearranged in the first direction Dx and the second direction Dy in amatrix having a row-column configuration in the display region 20. Eachof the detection electrodes DE is rectangular or square in the planview. The detection electrode DE is made of, for example, alight-transmitting conductive material such as indium tin oxide (ITO).

In the example illustrated in FIG. 6, for example, a plurality ofdetection electrodes DE(1,1), DE(1,2), . . . , DE(1,n) are arranged inthe second direction Dy. A plurality of detection electrodes DE(1,1), .. . , DE(m,1) are arranged in the first direction Dx. In the same way, aplurality of detection electrodes DE(m,1), . . . , DE(m,n) are arrangedin the second direction Dy. The detection electrodes DE(1,1), . . . ,DE(m,n) are each simply referred to as “detection electrode DE” whenthey need not be mentioned in a distinguished manner. In the firstembodiment, the example is illustrated in which m is 12 and n is 16.However, the values of m and n are not limited to those values. Thevalue of m may be any value, and the value of n may also be any value.

A plurality of the pixel electrodes 22 are arranged in a matrix having arow-column configuration in a position corresponding to each of thedetection electrodes DE. The pixel electrode 22 has an area smaller thanthat of the detection electrode DE. Although FIG. 6 illustrates some ofthe detection electrodes DE and the pixel electrodes 22, the detectionelectrodes DE and the pixel electrodes 22 are arranged over the entirearea of the display region 20. In this way, the detection electrode DEare provided in the area overlapping the display region 20. In thepresent disclosure, the row direction is also called the first directionDx, and the column direction is also called the second direction Dy.

The arrangement of the pixel electrodes 22 can not only be the matrixarrangement in which the pixel electrodes 22 are arranged in the firstdirection Dx and the second direction Dy intersecting the firstdirection Dx, but also employ a configuration in which the pixelelectrodes 22 facing each other are arranged so as to be displaced fromeach other in the first direction Dx or the second direction Dy. Aconfiguration can also be employed in which, using a difference in sizebetween the pixel electrodes 22 facing each other, two or three of thepixel electrode 22 are arranged on one side of one of the pixelelectrodes 22 included in a pixel array arranged in the first directionDx.

The coupling circuit 200 is provided on a short side of the peripheralregion 18. A circuit board 16 is coupled to the short side of theperipheral region 18. The circuit board 16 includes, for example,flexible printed circuits (FPC). The circuit board 16 is bonded to thefirst substrate 21, for example, with a film-on-glass (FOG) method usingan anisotropic conductive film (ACF) (hereinafter, called “FOGmounted”). This configuration electrically couples lines of wiring ofthe first substrate 21 to the lines of wiring of the circuit board 16corresponding to the lines of wiring of the first substrate 21.

The drive circuit 19 is provided on the circuit board 16. As illustratedin FIG. 1, the drive circuit 19 includes the control circuit 11, thedetection circuit 40, the analog front end 17, and the output circuit100. The drive circuit 19 is mounted on the circuit board 16, forexample, with a chip-on-film (COF) method using an ACF (hereinafter,called “COF mounted”). The drive circuit 19 is not limited to thisexample, and may be chip-on-glass (COG) mounted on the first substrate21. If the drive circuit 19 is COG mounted, the drive circuit 19 isprovided between the coupling circuit 200 and an FOG terminal to whichthe circuit board 16 is coupled. Some of the functions of the detectioncircuit 40 may be included in another integrated circuit for detection,or included as functions of an external microprocessing unit (MPU). Thedrive circuit 19 is not limited to the above mounting forms, and may beprovided, for example, on a control board outside the module.

The detection electrodes DE are electrically coupled to the drivecircuit 19 through detection electrode wiring 51, the coupling circuit200, first common wiring 52, and second common wiring 53. A plurality oflines of the detection electrode wiring 51 are electrically coupled tothe respective detection electrodes DE arranged in the display region20, and are lead out to the peripheral region 18. Each of the lines ofthe detection electrode wiring 51 extends along the second direction Dy,and the lines of the detection electrode wiring 51 are arranged in thefirst direction Dx.

The following describes a pixel array of the display panel 10. FIG. 7 isa circuit diagram illustrating the pixel array of the display regionaccording to the first embodiment.

The display region 20 illustrated in FIG. 7 include the sub-pixels SPixarranged in a matrix having a row-column configuration. Each of thesub-pixels SPix includes a switching element TrD and a liquid crystalLC. The switching element TrD is made of a thin film transistor, and inthe example, is made of an n-channel metal-oxide-semiconductor (MOS)TFT. The insulating layer 24 is provided between the pixel electrode 22and the detection electrode DE, and these components provide a storagecapacitor Cs illustrated in FIG. 7.

The switching elements TrD of the respective sub-pixels SPix, pixelsignal wiring 50, and the gate lines GCL illustrated in FIG. 7 areformed on the first substrate 21 (refer to FIG. 5). The pixel signalwiring 50 is wiring for supplying the pixel signal Vpix to each of thepixel electrodes 22. The gate lines GCL are wiring for supplying thedrive signals to drive the respective switching elements TrD. The pixelsignal wiring 50 and the gate lines GCL extend in a plane parallel tothe surface of the first substrate 21.

In the color filter 32 illustrated in FIG. 5, for example, color regionscolored in three colors of red (R), green (G), and blue (B) may beperiodically arranged. Color regions 32R, 32G, and 32B for the threecolors of R, G, and B are associated, as one set, with each set of thesub-pixels SPix illustrated in FIG. 7 described above. The sub-pixelsSPix corresponding to the color regions 32R, 32G, and 32B for the threecolors constitute, as one set, the pixel Pix. The color filter 32 mayinclude color regions for four or more colors.

The switching element TrD of each of the sub-pixels SPix is electricallycoupled to the drive circuit 19 through the pixel signal wiring 50, thecoupling circuit 200, the first common wiring 52, and the second commonwiring 53. A plurality of lines of the pixel signal wiring 50 are leadout to the peripheral region 18. Each of the lines of the pixel signalwiring 50 extends along the second direction Dy, and the lines of thepixel signal wiring 50 are arranged in the first direction Dx.

In the present embodiment, the pixel signal wiring 50 and the detectionelectrode wiring 51 are provided in different layers of the arraysubstrate 2. A layer provided with the pixel signal wiring 50 and alayer provided with the detection electrode wiring 51 are arranged inthe third direction Dz so as to overlap each other. The detectionelectrode wiring 51 and the pixel signal wiring 50 are not limited tothis example, and may be formed in the same layer.

The gate scanner circuit 12 illustrated in FIG. 1 sequentially selectseach of the gate lines GCL. The gate scanner circuit 12 applies the scansignal Vscan through the selected gate line GCL to the gate of theswitching element TrD of the sub-pixel SPix. This operation sequentiallyselects each row (each horizontal line) of the sub-pixels SPix as thetarget of display driving. The source driver 13 supplies the pixelsignal Vpix corresponding to each of the pixels Pix included in theselected horizontal line. The pixel signal Vpix is subjected totime-division processing on an individual sub-pixel SPix basis, theindividual sub-pixel being included in the pixels Pix; and thetime-divided signal is supplied through the pixel signal wiring 50. Withthe sub-pixels SPix described above, the display is performed horizontalline by horizontal line in response to the supplied pixel signal Vpix.

When the display operation is performed, the drive electrode driver 14applies the display drive signal VCOM to all the detection electrodesDE. The display drive signal VCOM is a voltage signal that serves as acommon potential for the sub-pixels SPix. As a result, the detectionelectrodes DE serve as the common electrode for the pixel electrodes 22during the display operation. During the display, the drive electrodedriver 14 applies the display drive signal VCOM to all the detectionelectrodes DE in the display region 20.

FIG. 8 is a perspective view illustrating an arrangement example of thedetection electrodes. As illustrated in FIG. 8, outer frame wiring 55 isprovided in the peripheral region 18 on one surface 21 a side of thefirst substrate 21. For example, the outer frame wiring 55 iscontinuously provided along long sides and short sides of the displayregion 20, and surrounds the display region 20. The outer frame wiring55 may be supplied with the guard signal Vgd when the display device 1detects whether the detection target object is in the present state.

FIG. 9 is a diagram illustrating a time division example between thedisplay mode and the detection mode in the display device according tothe first embodiment.

In the present embodiment, an operation in the display mode during adisplay period Pd and an operation in the detection mode during adetection period Pt are alternately performed in a time-division manner.In the example illustrated in FIG. 9, in a one-frame period of the videosignal Vdisp, a one-frame period in the display mode is divided intofour display periods Pd1, Pd2, Pd3, and Pd4. In the example illustratedin FIG. 9, in the one-frame period of the video signal Vdisp, aone-frame period in the detection mode is half the one-frame period ofthe video signal Vdisp. In the example illustrated in FIG. 9, an exampleis illustrated in which a detection period Pt1 is provided between thedisplay period Pd1 and the display period Pd2, and a detection periodPt2 is provided between the display period Pd2 and the display periodPd3.

Hereinafter, the display periods Pd1, Pd2, Pd3, and Pd4 are each simplycalled “display period Pd” when they need not be distinguished from oneanother.

FIGS. 10A to 10D are explanatory diagrams for explaining states wherethe detection electrodes supplied with the detection input/outputsignals are sequentially selected and switched. FIG. 11 is a diagramillustrating an example of the detection periods during which thedetection input/output signals are supplied to the respective detectionelectrodes.

In the present embodiment, as illustrated in FIGS. 10A to 10D, four ofthe detection electrodes DE arranged adjacent to one another in thefirst direction Dx are treated as one unit, and each of the detectionelectrodes DE(1,4), DE(1,3), DE(1,2), and DE(1,1) is sequentiallyselected and supplied with the detection input/output signal AFE in atime-division manner.

In a detection period Pt1(1,4) illustrated in FIG. 11, the detectionelectrode DE(1,4) is selected (refer to FIG. 10A). In the detectionperiod Pt1(1,4), the detection input/output signal AFE is supplied tothe detection electrode DE(1,4), and the guard signal Vgd is supplied tothe detection electrodes DE(1,3), DE(1,1), and DE(1,2).

In a detection period Pt1(1,3) illustrated in FIG. 11, the detectionelectrode DE(1,3) is selected (refer to FIG. 10B). In the detectionperiod Pt1(1,3), the detection input/output signal AFE is supplied tothe detection electrode DE(1,3), and the guard signal Vgd is supplied tothe detection electrodes DE(1,4), DE(1,1), and DE(1,2).

In a detection period Pt2(1,2) illustrated in FIG. 11, the detectionelectrode DE(1,2) is selected (refer to FIG. 10C). In the detectionperiod Pt2(1,2), the detection input/output signal AFE is supplied tothe detection electrode DE(1,2), and the guard signal Vgd is supplied tothe detection electrodes DE(1,3), DE(1,4), and DE(1,1).

In a detection period Pt2(1,1) illustrated in FIG. 11, the detectionelectrode DE(1,1) is selected (refer to FIG. 10D). In the detectionperiod Pt2(1,1), the detection input/output signal AFE is supplied tothe detection electrode DE(1,1), and the guard signal Vgd is supplied tothe detection electrodes DE(1,3), DE(1,4), and DE(1,2).

Hereinafter, the detection periods Pt1, Pt2, Pt1(1,4), Pt1(1,3),Pt2(1,2), and Pt2(1,1) are each simply called “detection period Pt” whenthey need not be distinguished from one another.

In the present disclosure, for example, the display periods, thedetection periods, and the number and switching order of the detectionelectrodes supplied with the detection input/output signal AFEhereinafter have the aspects illustrated in FIGS. 9 to 11. The aspectsof, for example, the display periods, the detection periods, and thenumber and switching order of the detection electrodes supplied with thedetection input/output signal AFE illustrated in FIGS. 9 to 11 are mereexamples, and are not limited to the above-described aspects.

The following describes differences between the display device accordingto the first embodiment and comparative examples. The followingdescription exemplifies the number of the lines of the pixel signalwiring 50 as 1080, and the number of the lines of the detectionelectrode wiring 51 as 648. The internal configurations and theoperations of the output circuit 100 and the coupling circuit 200 of thedisplay device 1 according to the first embodiment will be describedlater.

FIG. 12 is a block diagram illustrating a configuration example of adisplay device according to a first comparative example with respect tothe first embodiment. FIG. 13 is a diagram illustrating a configurationof an output circuit and a coupling circuit of the display deviceaccording to the first comparative example with respect to the firstembodiment. FIG. 14 is a diagram illustrating a timing control exampleof the display device according to the first comparative example withrespect to the first embodiment.

A display device 1 a according to the first comparative example withrespect to the first embodiment illustrated in FIG. 12 differs, ininternal configurations and operations of an output circuit 100 a and acoupling circuit 200 a, from the display device 1 according to the firstembodiment illustrated in FIG. 1.

In the first comparative example with respect to the first embodimentillustrated in FIG. 13, the output circuit 100 a includes a switchingcircuit 130 and a switching circuit 140. The output circuit 100 aincludes, for example, a multiplexer.

The switching circuit 130 switches between the display drive signalVCOM, the detection input/output signal AFE, and the guard signal Vgd.The switching circuit 130 includes a switch SW131, a switch SW132, and aswitch SW133.

The switching circuit 140 switches between the pixel signal Vpix and theguard signal Vgd. The switching circuit 140 includes a switch SW141 anda switch SW142.

In the first comparative example with respect to the first embodimentillustrated in FIG. 13, the coupling circuit 200 a includes a switchingcircuit 230. The coupling circuit 200 a includes, for example, amultiplexer.

The switching circuit 230 outputs the pixel signal Vpix in atime-division manner to the respective sub-pixels SPix constituting eachof the pixels Pix. Herein, for ease of explanation, one switch SW231 isillustrated.

The following describes control states of the respective switches in thedisplay period Pd of the display device 1 a according to the firstcomparative example with respect to the first embodiment.

As illustrated in FIG. 14, in the display period Pd, each of theswitches SW142, SW131, and SW231 is controlled to be on, and each of theswitches SW132, SW133, and SW141 is controlled to be off. As a result,the pixel signal Vpix is applied to the pixel signal wiring 50, and thedisplay drive signal VCOM is applied to the detection electrode wiring51.

The following describes the control states of the respective switches inthe detection period Pt of the display device 1 a according to the firstcomparative example with respect to the first embodiment.

As illustrated in FIG. 14, in the detection period Pt, the switchesSW141 and SW231, the switches SW132 corresponding to the non-selecteddetection electrodes DE, and the switch SW133 corresponding to theselected detection electrode DE are each controlled to be on. In thedetection period Pt, the switch SW142, the switch SW132 corresponding tothe selected detection electrode DE, and the switches SW133corresponding to the non-selected detection electrodes DE are eachcontrolled to be off. As a result, the guard signal Vgd is applied tothe pixel signal wiring 50. The detection input/output signal AFE isapplied to a line of the detection electrode wiring 51 corresponding tothe selected detection electrode DE, and the guard signal Vgd is appliedto lines of the detection electrode wiring 51 corresponding to thenon-selected detection electrodes DE.

Specifically, in the detection period Pt1(1,4), the switches SW141 andSW231, the switches SW132(1,3), SW132(1,1), and SW132(1,2) correspondingto the non-selected detection electrodes DE(1,3), DE(1,1), and DE(1,2),and the switch SW133(1,4) corresponding to the selected detectionelectrode DE(1,4) are each controlled to be on. In the detection periodPt1(1,4), the switch SW142, the switch SW132(1,4) corresponding to theselected detection electrode DE(1,4), and the switches SW133(1,3),SW133(1,1), and SW133(1,2) corresponding to the non-selected detectionelectrodes DE(1,3), DE(1,1), and DE(1,2) are each controlled to be off.

In the detection period Pt1(1,3), the switches SW141 and SW231, theswitches SW132(1,4), SW132(1,1), and SW132(1,2) corresponding to thenon-selected detection electrodes DE(1,4), DE(1,1), and DE(1,2), and theswitch SW133(1,3) corresponding to the selected detection electrodeDE(1,3) are each controlled to be on. In the detection period Pt1(1,3),the switch SW142, the switch SW132(1,3) corresponding to the selecteddetection electrode DE(1,3), and the switches SW133(1,4), SW133(1,1),and SW133(1,2) corresponding to the non-selected detection electrodesDE(1,4), DE(1,1), and DE(1,2) are each controlled to be off.

In the detection period Pt2(1,2), the switches SW141 and SW231, theswitches SW132(1,3), SW132(1,4), and SW132(1,1) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,4), and DE(1,1), and theswitch SW133(1,2) corresponding to the selected detection electrodeDE(1,2) are each controlled to be on. In the detection period Pt2(1,2),the switch SW142, the switch SW132(1,2) corresponding to the selecteddetection electrode DE(1,2), and the switches SW133(1,3), SW133(1,4),and SW133(1,1) corresponding to the non-selected detection electrodesDE(1,3), DE(1,4), and DE(1,1) are each controlled to be off.

In the detection period Pt2(1,1), the switches SW141 and SW231, theswitches SW132(1,3), SW132(1,4), and SW132(1,2) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,4), and DE(1,2), and theswitch SW133(1,1) corresponding to the selected detection electrodeDE(1,1) are each controlled to be on. In the detection period Pt2(1,1),the switch SW142, the switch SW132(1,1) corresponding to the selecteddetection electrode DE(1,1), and the switches SW133(1,3), SW133(1,4),and SW133(1,2) corresponding to the non-selected detection electrodesDE(1,3), DE(1,4), and DE(1,2) are each controlled to be off.

FIG. 15 is a block diagram illustrating a configuration example of adisplay device according to a second comparative example with respect tothe first embodiment. FIG. 16 is a diagram illustrating a configurationof an output circuit and a coupling circuit of the display deviceaccording to the second comparative example with respect to the firstembodiment. FIG. 17 is a diagram illustrating a timing control exampleof the display device according to the second comparative example withrespect to the first embodiment.

A display device 1 b according to the second comparative example withrespect to the first embodiment illustrated in FIG. 15 differs from thedisplay device 1 according to the first embodiment illustrated in FIG. 1in internal configurations and operations of an output circuit 100 b anda coupling circuit 200 b. In the second comparative example with respectto the first embodiment, an analog front end 17 a outputs the detectioninput/output signals AFE of 36 systems obtained by dividing the 648lines of the detection electrode wiring 51 by 18. The detectioninput/output signals AFE of the 36 systems are temporally divided by ashift register (SR) 300, and supplied to the coupling circuit 200 b.

In the second comparative example with respect to the first embodimentillustrated in FIG. 16, the output circuit 100 b includes a switchingcircuit 110 and the switching circuit 140. The output circuit 100 bincludes, for example, a multiplexer.

The switching circuit 110 switches between the display drive signal VCOMand the guard signal Vgd. The switching circuit 110 includes a switchSW111 and a switch SW112.

In the second comparative example with respect to the first embodimentillustrated in FIG. 16, the coupling circuit 200 b includes a switchingcircuit 220 and a switching circuit 240. The coupling circuit 200 bincludes, for example, a multiplexer.

The switching circuit 220 outputs the pixel signal Vpix in atime-division manner to the respective sub-pixels SPix constituting eachof the pixels Pix. Herein, for ease of explanation, one switch SW221 isillustrated.

The switching circuit 240 switches between the display drive signal VCOMor the guard signal Vgd selected by the switching circuit 110 and thedetection input/output signal AFE. The switching circuit 240 includes aswitch SW241 and a switch SW242.

The following describes the control states of the respective switches inthe display period Pd of the display device 1 b according to the secondcomparative example with respect to the first embodiment.

As illustrated in FIG. 17, in the display period Pd, each of theswitches SW111, SW142, SW221, and SW241 is controlled to be on, and eachof the switches SW112, SW141, and SW242 is controlled to be off. As aresult, the pixel signal Vpix is applied to the pixel signal wiring 50,and the display drive signal VCOM is applied to the detection electrodewiring 51.

The following describes the control states of the respective switches inthe detection period Pt of the display device 1 b according to thesecond comparative example with respect to the first embodiment.

As illustrated in FIG. 17, in the detection period Pt, the switchesSW112 and SW141, the switches SW241 corresponding to the non-selecteddetection electrodes DE, and the switch SW242 corresponding to theselected detection electrode DE are each controlled to be on. In thedetection period Pt, the switches SW111, SW142, and SW221, the switchSW241 corresponding to the selected detection electrode DE, and theswitches SW242 corresponding to the non-selected detection electrodes DEare each controlled to be off. As a result, the detection input/outputsignal AFE is applied to a line of the detection electrode wiring 51corresponding to the selected detection electrode DE, and the guardsignal Vgd is applied to lines of the detection electrode wiring 51corresponding to the non-selected detection electrodes DE.

Specifically, in the detection period Pt1(1,4), the switches SW112 andSW141, the switches SW241(1,3), SW241(1,1), and SW241(1,2) correspondingto the non-selected detection electrodes DE(1,3), DE(1,1), and DE(1,2),and the switch SW242(1,4) corresponding to the selected detectionelectrode DE(1,4) are each controlled to be on. In the detection periodPt1(1,4), the switches SW111, SW142, and SW221, the switch SW241(1,4)corresponding to the selected detection electrode DE(1,4), and theswitches SW242(1,3), SW242(1,1), and SW242(1,2) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,1), and DE(1,2) are eachcontrolled to be off.

In the detection period Pt1(1,3), the switches SW112 and SW141, theswitches SW241(1,4), SW241(1,1), and SW241(1,2) corresponding to thenon-selected detection electrodes DE(1,4), DE(1,1), and DE(1,2), and theswitch SW242(1,3) corresponding to the selected detection electrodeDE(1,3) are each controlled to be on. In the detection period Pt1(1,3),the switches SW111, SW142, and SW221, the switch SW241(1,3)corresponding to the selected detection electrode DE(1,3), and theswitches SW242(1,4), SW242(1,1), and SW242(1,2) corresponding to thenon-selected detection electrodes DE(1,4), DE(1,1), and DE(1,2) are eachcontrolled to be off.

In the detection period Pt2(1,2), the switches SW112 and SW141, theswitches SW241(1,3), SW241(1,4), and SW241(1,1) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,4), and DE(1,1), and theswitch SW242(1,2) corresponding to the selected detection electrodeDE(1,2) are each controlled to be on. In the detection period Pt2(1,2),the switches SW111, SW142, and SW221, the switch SW241(1,2)corresponding to the selected detection electrode DE(1,2), and theswitches SW242(1,3), SW242(1,4), and SW242(1,1) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,4), and DE(1,1) are eachcontrolled to be off.

In the detection period Pt2(1,1), the switches SW112 and SW141, theswitches SW241(1,3), SW241(1,4), and SW241(1,2) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,4), and DE(1,2), and theswitch SW242(1,1) corresponding to the selected detection electrodeDE(1,1) are each controlled to be on. In the detection period Pt2(1,1),the switches SW111, SW142, and SW221, the switch SW241(1,1)corresponding to the selected detection electrode DE(1,1), and theswitches SW242(1,3), SW242(1,4), and SW242(1,2) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,4), and DE(1,2) are eachcontrolled to be off.

FIG. 18 is a diagram illustrating a configuration of the output circuitand the coupling circuit of the display device according to the firstembodiment. FIG. 19 is a diagram illustrating a timing control exampleof the display device according to the first embodiment.

As illustrated in FIG. 18, the output circuit 100 of the display device1 according to the first embodiment includes the switching circuit 110and a switching circuit 120. The output circuit 100 includes, forexample, a multiplexer.

The switching circuit 110 switches between the display drive signal VCOMand the guard signal Vgd, and outputs the selected signal to the secondcommon wiring 53. The switching circuit 110 includes the switch SW111and the switch SW112.

The switching circuit 120 switches between the pixel signal Vpix, theguard signal Vgd, and the detection input/output signal AFE, and outputsthe selected signal to the first common wiring 52. The switching circuit120 includes a switch SW121, a switch SW122, and a switch SW123.

As illustrated in FIG. 18, the coupling circuit 200 of the displaydevice 1 according to the first embodiment includes a switching circuit210 (second switching circuit) and the switching circuit 220 (firstswitching circuit). The coupling circuit 200 includes, for example, amultiplexer.

The switching circuit 210 (second switching circuit) switches betweenthe display drive signal VCOM or the guard signal Vgd that has beenselected by the switching circuit 110 and output to the second commonwiring 53 and the pixel signal Vpix or the detection input/output signalAFE output to the first common wiring 52 by the switching circuit 120.The switching circuit 210 (second switching circuit) includes a switchSW211 and a switch SW212.

The switching circuit 220 (first switching circuit) outputs the pixelsignal Vpix in a time-division manner to the respective sub-pixels SPixconstituting each of the pixels Pix through the pixel signal wiring 50.Herein, for ease of explanation, one switch SW221 is illustrated.

The following describes the control states of the respective switches inthe display period Pd of the display device 1 according to the firstembodiment.

As illustrated in FIG. 19, in the display period Pd, each of theswitches SW111, SW123, SW211, and SW221 is controlled to be on, and eachof the switches SW112, SW121, SW122, and SW212 is controlled to be off.As a result, the pixel signal Vpix is applied to the pixel signal wiring50, and the display drive signal VCOM is applied to the detectionelectrode wiring 51.

The following describes the control states of the respective switches inthe detection period Pt of the display device 1 according to the firstembodiment.

As illustrated in FIG. 19, in the detection period Pt, the switchesSW112 and SW212, the switches SW121 corresponding to the non-selecteddetection electrodes DE, and the switch SW122 corresponding to theselected detection electrode DE are each controlled to be on. In thedetection period Pt, the switches SW111, SW123, SW211, and SW221, theswitch SW121 corresponding to the selected detection electrode DE, andthe switches SW122 corresponding to the non-selected detectionelectrodes DE are each controlled to be off. As a result, the detectioninput/output signal AFE is applied to a line of the detection electrodewiring 51 corresponding to the selected detection electrode DE, and theguard signal Vgd is applied to lines of the detection electrode wiring51 corresponding to the non-selected detection electrodes DE.

Specifically, in the detection period Pt1(1,4), the switches SW112 andSW212, the switches SW121(1,3), SW121(1,1), and SW121(1,2) correspondingto the non-selected detection electrodes DE(1,3), DE(1,1), and DE(1,2),and the switch SW122(1,4) corresponding to the selected detectionelectrode DE(1,4) are each controlled to be on. In the detection periodPt1(1,4), the switches SW111, SW123, SW211, and SW221, the switchSW121(1,4) corresponding to the selected detection electrode DE(1,4),and the switches SW122(1,3), SW122(1,1), and SW122(1,2) corresponding tothe non-selected detection electrodes DE(1,3), DE(1,1), and DE(1,2) areeach controlled to be off.

In the detection period Pt1(1,3), the switches SW112 and SW212, theswitches SW121(1,4), SW121(1,1), and SW121(1,2) corresponding to thenon-selected detection electrodes DE(1,4), DE(1,1), and DE(1,2), and theswitch SW122(1,3) corresponding to the selected detection electrodeDE(1,3) are each controlled to be on. In the detection period Pt1(1,3),the switches SW111, SW123, SW211, and SW221, the switch SW121(1,3)corresponding to the selected detection electrode DE(1,3), and theswitches SW122(1,4), SW122(1,1), and SW122(1,2) corresponding to thenon-selected detection electrodes DE(1,4), DE(1,1), and DE(1,2) are eachcontrolled to be off.

In the detection period Pt2(1,2), the switches SW112 and SW212, theswitches SW121(1,3), SW121(1,4), and SW121(1,1) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,4), and DE(1,1), and theswitch SW122(1,2) corresponding to the selected detection electrodeDE(1,2) are each controlled to be on. In the detection period Pt2(1,2),the switches SW111, SW123, SW211, and SW221, the switch SW121(1,2)corresponding to the selected detection electrode DE(1,2), and theswitches SW122(1,3), SW122(1,4), and SW122(1,1) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,4), and DE(1,1) are eachcontrolled to be off.

In the detection period Pt2(1,1), the switches SW112 and SW212, theswitches SW121(1,3), SW121(1,4), and SW121(1,2) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,4), and DE(1,2), and theswitch SW122(1,1) corresponding to the selected detection electrodeDE(1,1) are each controlled to be on. In the detection period Pt2(1,1),the switches SW111, SW123, SW211, and SW221, the switch SW121(1,1)corresponding to the selected detection electrode DE(1,1), and theswitches SW122(1,3), SW122(1,4), and SW122(1,2) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,4), and DE(1,2) are eachcontrolled to be off.

In the present embodiment, the configuration has been exemplified inwhich the switching circuit 110 is included, and the switching circuit210 (second switching circuit) receives the display drive signal VCOM orthe guard signal Vgd selected by the switching circuit 110. However, theconfiguration may be such that the switching circuit 110 is fixed at thedisplay drive signal VCOM, that is, the display drive signal VCOM issupplied to the switching circuit 210 (second switching circuit) even inthe detection period Pt. Alternatively, an aspect may be such that theswitching circuit 110 is not provided, and the display drive signal VCOMis supplied to the second common wiring 53.

In the present embodiment, as described above, the pixel signal wiring50 includes 1080 lines, and the detection electrode wiring 51 includes648 lines. In this case, an aspect may be such that a plurality of linesof the pixel signal wiring 50 are assigned to each line of the detectionelectrode wiring 51.

In the configuration according to the first comparative example withrespect to the first embodiment, the number of lines of the wiringbetween the output circuit 100 a and the coupling circuit 200 a is thesame as the total number of lines of the pixel signal wiring 50 and thedetection electrode wiring 51. In contrast, in the display device 1according to the first embodiment, the number of lines of the wiringbetween the output circuit 100 and the coupling circuit 200, that is,the total number of lines of the first common wiring 52 and the secondcommon wiring 53 can be smaller than the total number of lines of thepixel signal wiring 50 and the detection electrode wiring 51.Specifically, when, for example, the pixel signal wiring 50 includes1080 lines and the detection electrode wiring 51 includes 648 lines, thenumber of line of wiring between the output circuit 100 a and thecoupling circuit 200 a is 1728 in the configuration according to thefirst comparative example with respect to the first embodiment. However,in the display device 1 according to the first embodiment, the number oflines of the wiring between the output circuit 100 and the couplingcircuit 200 can be 1081.

In the configuration according to the second comparative example withrespect to the first embodiment, the number of lines of the wiringbetween the output circuit 100 b and the coupling circuit 200 b issmaller than that in the configuration according to the firstcomparative example with respect to the first embodiment. However, asdescribed above, in the configuration according to the secondcomparative example with respect to the first embodiment, the detectioninput/output signals AFE need to be divided by 18 using the shiftregister 300 (SR), and the same number of the detection input/outputsignals AFE as the number of lines of the detection electrode wiring 51need to be generated. The circuit scale of the multiplexer (notillustrated) for generating a control signal for controlling the switchSW240 of the switching circuit 240 may increase.

With the configuration of the display device 1 according to the firstembodiment, the configuration illustrated in FIG. 18 and the timingcontrol illustrated in FIG. 19 allow both the pixel signal Vpix that issupplied to the pixel Pix and the detection input/output signal AFE thatis supplied to the detection electrode DE to be transmitted through thefirst common wiring 52. Specifically, the pixel signal Vpix is suppliedthrough the first common wiring 52 in the display period Pd, and thedetection input/output signal AFE is supplied through the first commonwiring 52 in the detection period Pt. The pixel signal Vpix is appliedto the pixel signal wiring 50 in the display period Pd, and thedetection input/output signal AFE is applied to the detection electrodewiring 51 in the detection period Pt. This configuration can reduce thenumber of lines of the wiring coupled to the display panel 10, and canreduce the width of the peripheral region 18 outside the display region20 and the width of the coupling portion between the display panel 10and the circuit board 16.

Modification of First Embodiment

FIG. 20 is a block diagram illustrating a configuration example of adisplay device according to a modification of the first embodiment. FIG.21 is a diagram illustrating a configuration of the output circuit and acoupling circuit of the display device according to the modification ofthe first embodiment. FIG. 22 is a diagram illustrating a timing controlexample of the display device according to the modification of the firstembodiment. The output circuit 100 of a display device 1 c according tothe modification of the first embodiment is the same as that of thedisplay device 1 according to the first embodiment, and therefore, willnot be described below.

As illustrated in FIG. 21, in the display device 1 c according to themodification of the first embodiment, the display drive signal VCOM orthe guard signal Vgd selected by the switching circuit 110 is suppliedto the outer frame wiring 55 provided in the peripheral region 18.

As illustrated in FIG. 21, a coupling circuit 200 c of the displaydevice 1 c according to the modification of the first embodiment furtherincludes a switching circuit 250 (third switching circuit) in additionto the above-described configuration of the display device 1 accordingto the first embodiment.

The switching circuit 250 (third switching circuit) couples the displaydrive signal VCOM or the guard signal Vgd selected by the switchingcircuit 110 to the pixel signal wiring 50. The switching circuit 250(third switching circuit) includes a switch SW251. The switches SW251are provided so as to correspond to the sub-pixels SPix constitutingeach of the pixels Pix. Herein, however, for ease of explanation, one ofthe switches SW251 is illustrated.

As illustrated in FIG. 22, the switch SW251 is controlled to be off inthe display period Pd, and controlled to be on in the detection periodPt. As a result, the guard signal Vgd is applied to the pixel signalwiring 50 in the detection period Pt.

With the configuration of the first embodiment described above, thepixel signal wiring 50 is placed in the floating state and is set tohigh impedance HiZ in the detection period Pt (refer to FIG. 19).

In the display device 1 according to the first embodiment, when astandby state continues in which no screen display is made, thepotential of the pixel signal wiring 50 set to the high impedance HiZ isvaried by a leak current generated between the pixel signal wiring 50and the gate of the switching element TrD of each of the sub-pixel SPix,and what is called burn-in may occur. With the configuration of thefirst comparative example with respect to the first embodimentillustrated in FIGS. 12 to 14, the pixel signal wiring 50 can be avoidedfrom being in the floating state by controlling the switch SW231 of theswitching circuit 230 (first switching circuit) in the detection periodPt to be on.

With the configuration of the first embodiment, the detectioninput/output signal AFE is applied to the first common wiring 52 in thedetection period Pt. As a result, when the switch SW221 of the switchingcircuit 220 (first switching circuit) is controlled to be on in thedetection period Pt, the detection input/output signal AFE is suppliedto the pixel signal wiring 50, and the accuracy of the touch detectionmay decrease. With the configuration of the first embodiment, as amethod for restraining the occurrence of the burn-in, it is conceivableto turn on the switch SW221 of the switching circuit 220 (firstswitching circuit) at predetermined intervals of time when the standbystate is established in which no screen display is made.

In the display device 1 c according to the modification of the firstembodiment, the switch SW251 is controlled to be on in the detectionperiod Pt. As a result, the pixel signal wiring 50 can be avoided frombeing in the floating state, and the burn-in can be prevented fromoccurring in the standby state in which no screen display is made.

As described above, the display device 1 according to the firstembodiment includes the display panel 10 provided with the displayregion 20 including the pixels Pix and with the detection electrodes.The display panel 10 includes the lines of the first common wiring 52each of which transmits the pixel signal Vpix to be supplied to thepixel Pix or the detection input/output signal AFE to be supplied to thedetection electrode DE, the pixel signal wiring 50 electrically coupledto the pixels Pix, the detection electrode wiring 51 electricallycoupled to the detection electrodes DE, the switching circuit 220 (firstswitching circuit) that electrically couples or uncouples the firstcommon wiring 52 to or from the pixel signal wiring 50, and theswitching circuit 210 (second switching circuit) that electricallycouples or uncouples the first common wiring 52 to or from the detectionelectrode wiring 51.

In the above-described configuration, the pixel signal Vpix istransmitted to the first common wiring 52 in the display period Pd, andthe detection input/output signal AFE is transmitted to the first commonwiring 52 in the detection period Pt. The switching circuit 220 (firstswitching circuit) applies the pixel signal Vpix to the pixel signalwiring 50 in the display period Pd. The switching circuit 210 (secondswitching circuit) applies the detection input/output signal AFE to thedetection electrode wiring 51 in the detection period Pt.

The display device 1 according to the first embodiment includes thesecond common wiring 53 that transmits the display drive signal VCOM tobe supplied to the detection electrode DE. The switching circuit 210(second switching circuit) electrically couples or uncouples the secondcommon wiring 53 to or from the detection electrode DE, and applies thedisplay drive signal VCOM to the detection electrode wiring 51 in thedisplay period Pd.

In the above-described configuration, the detection input/output signalAFE or the guard signal Vgd is transmitted to the first common wiring 52in the detection period Pt. The switching circuit 210 (second switchingcircuit) applies the detection input/output signal AFE or the guardsignal Vgd to the detection electrode wiring 51 in the detection periodPt.

The display device 1 according to the first embodiment can transmit,through the first common wiring 52, both the pixel signal Vpix to besupplied to the pixel Pix and the detection input/output signal AFE tobe supplied to the detection electrode DE. This configuration can reducethe number of lines of the wiring coupled to the display panel 10, andcan reduce the width of the peripheral region 18 outside the displayregion 20 and the width of the coupling portion between the displaypanel 10 and the circuit board 16.

In the display device 1 c according to the modification of the firstembodiment, the outer frame wiring 55 electrically coupled to the secondcommon wiring 53 is provided in the peripheral region 18 outside thedisplay region 20. The coupling circuit 200 c further includes theswitching circuit 250 (third switching circuit) that electricallycouples or uncouples the outer frame wiring 55 to or from the pixelsignal wiring 50. The switching circuit 250 (third switching circuit)applies the guard signal Vgd to the pixel signal wiring 50 in thedetection period Pt.

With the display device 1 c according to the modification of the firstembodiment, the pixel signal wiring 50 can be avoided from being in thefloating state, and the burn-in can be prevented from occurring in thestandby state in which no screen display is made.

The present embodiment can provide the display devices 1 and 1 c thatcan reduce the number of lines of the wiring coupled to the displaypanels 10 and 10 c.

Second Embodiment

Hereinafter, components having the same functions as those of theabove-described first embodiment will be given the same referencenumerals as those in the first embodiment, and will not be describedbelow. A display device of a second embodiment will be described mainlyin terms of differences from the first embodiment.

FIG. 23 is a block diagram illustrating a configuration example of thedisplay device according to the second embodiment. FIG. 24 is a diagramillustrating a configuration of an output circuit and a coupling circuitof the display device according to the second embodiment. FIG. 25 is adiagram illustrating a timing control example of the display deviceaccording to the second embodiment.

As illustrated in FIG. 24, an output circuit 100 c of a display device 1d according to the second embodiment includes the switching circuit 110and a switching circuit 150. The output circuit 100 c includes, forexample, a multiplexer.

The switching circuit 150 switches between the pixel signal Vpix and thedetection input/output signal AFE, and outputs the selected signal tothe first common wiring 52. The switching circuit 150 includes a switchSW151 and a switch SW152.

As illustrated in FIG. 24, a coupling circuit 200 d of the displaydevice 1 d according to the second embodiment includes a switchingcircuit 260 (second switching circuit) and the switching circuit 220(first switching circuit). The coupling circuit 200 d includes, forexample, a multiplexer.

The switching circuit 260 (second switching circuit) switches betweenthe display drive signal VCOM or the guard signal Vgd that has beenselected by the switching circuit 110 and has been output to the secondcommon wiring 53 and the detection input/output signal AFE output to thefirst common wiring 52 by the switching circuit 150. The switchingcircuit 260 (second switching circuit) includes a switch SW261 and aswitch SW262.

The following describes the control states of the respective switches inthe display period Pd of the display device 1 d according to the secondembodiment.

As illustrated in FIG. 25, in the display period Pd, the switches SW111,SW151, SW261, and SW221 are controlled to be on, and the switches SW112,SW152, and SW262 are controlled to be off. As a result, the pixel signalVpix is applied to the pixel signal wiring 50, and the display drivesignal VCOM is applied to the detection electrode wiring 51.

The following describes the control states of the respective switches inthe detection period Pt of the display device 1 d according to thesecond embodiment.

As illustrated in FIG. 25, in the detection period Pt, the switch SW112,the switches SW261 corresponding to the non-selected detectionelectrodes DE, and the switch SW152 corresponding to the selecteddetection electrode DE are each controlled to be on. In the detectionperiod Pt, the switches SW111, SW151, and SW221, the switch SW261corresponding to the selected detection electrode DE, and the switchesSW152 corresponding to the non-selected detection electrodes DE are eachcontrolled to be off. As a result, the detection input/output signal AFEis applied to a line of the detection electrode wiring 51 correspondingto the selected detection electrode DE, and the guard signal Vgd isapplied to lines of the detection electrode wiring 51 corresponding tothe non-selected detection electrodes DE.

Specifically, in the detection period Pt1(1,4), the switch SW112, theswitches SW261(1,3), SW261(1,1), and SW261(1,2) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,1), and DE(1,2), and theswitch SW152(1,4) corresponding to the selected detection electrodeDE(1,4) are each controlled to be on. In the detection period Pt1(1,4),the switches SW111, SW151, and SW221, the switch SW261(1,4)corresponding to the selected detection electrode DE(1,4), and theswitches SW152(1,3), SW152(1,1), and SW152(1,2) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,1), and DE(1,2) are eachcontrolled to be off.

In the detection period Pt1(1,3), the switch SW112, the switchesSW261(1,4), SW261(1,1), and SW261(1,2) corresponding to the non-selecteddetection electrodes DE(1,4), DE(1,1), and DE(1,2), and the switchSW152(1,3) corresponding to the selected detection electrode DE(1,3) areeach controlled to be on. In the detection period Pt1(1,3), the switchesSW111, SW151, and SW221, the switch SW261(1,3) corresponding to theselected detection electrode DE(1,3), and the switches SW152(1,4),SW152(1,1), and SW152(1,2) corresponding to the non-selected detectionelectrodes DE(1,4), DE(1,1), and DE(1,2) are each controlled to be off.

In the detection period Pt2(1,2), the switch SW112, the switchesSW261(1,3), SW261(1,4), and SW261(1,1) corresponding to the non-selecteddetection electrodes DE(1,3), DE(1,4), and DE(1,1), and the switchSW152(1,2) corresponding to the selected detection electrode DE(1,2) areeach controlled to be on. In the detection period Pt2(1,2), the switchesSW111, SW151, and SW221, the switch SW261(1,2) corresponding to theselected detection electrode DE(1,2), and the switches SW152(1,3),SW152(1,4), and SW152(1,1) corresponding to the non-selected detectionelectrodes DE(1,3), DE(1,4), and DE(1,1) are each controlled to be off.

In the detection period Pt2(1,1), the switch SW112, the switchesSW261(1,3), SW261(1,4), and SW261(1,2) corresponding to the non-selecteddetection electrodes DE(1,3), DE(1,4), and DE(1,2), and the switchSW152(1,1) corresponding to the selected detection electrode DE(1,1) areeach controlled to be on. In the detection period Pt2(1,1), the switchesSW111, SW151, and SW221, the switch SW261(1,1) corresponding to theselected detection electrode DE(1,1), and the switches SW152(1,3),SW152(1,4), and SW152(1,2) corresponding to the non-selected detectionelectrodes DE(1,3), DE(1,4), and DE(1,2) are each controlled to be off.

Also in the display device 1 d according to the second embodiment, theconfiguration can be such that the burn-in is prevented from occurringin the standby state in which no screen display is made, in the same wayas the configuration according to the modification of the firstembodiment. Specifically, the configuration further includes theswitching circuit 250 (third switching circuit). The display drivesignal VCOM or the guard signal Vgd selected by the switching circuit110 is supplied to the outer frame wiring 55 provided in the peripheralregion 18, and the switch SW251 is controlled to be on in the detectionperiod Pt. This configuration allows the pixel signal wiring 50 to avoidfrom being in the floating state.

With the configuration of the display device 1 d according to the secondembodiment, the configuration illustrated in FIG. 24 and the timingcontrol illustrated in FIG. 25 allow both the pixel signal Vpix that issupplied to the pixel Pix and the detection input/output signal AFE thatis supplied to the detection electrode DE to be transmitted through thefirst common wiring 52. Specifically, the pixel signal Vpix is suppliedthrough the first common wiring 52 in the display period Pd, and thedetection input/output signal AFE is supplied through the first commonwiring 52 in the detection period Pt. The pixel signal Vpix is appliedto the pixel signal wiring 50 in the display period Pd, and thedetection input/output signal AFE is applied to the detection electrodewiring 51 in the detection period Pt. This configuration can reduce thenumber of lines of the wiring coupled to a display panel 10 d, and canreduce the width of the peripheral region 18 outside the display region20 and the width of the coupling portion between the display panel 10 dand a circuit board 16 c.

As described above, the display device 1 d according to the secondembodiment includes the display panel 10 d provided with the displayregion 20 including the pixels Pix and with the detection electrodes.The display panel 10 d includes the lines of the first common wiring 52each of which transmits the pixel signal Vpix to be supplied to thepixel Pix or the detection input/output signal AFE to be supplied to thedetection electrode DE, the second common wiring 53 transmitting thedisplay drive signal VCOM to be supplied to the detection electrode DEand the guard signal Vgd synchronized with the detection input/outputsignal AFE, the pixel signal wiring 50 electrically coupled to thepixels Pix, the detection electrode wiring 51 electrically coupled tothe detection electrodes DE, the switching circuit 220 (first switchingcircuit) that electrically couples or uncouples the first common wiring52 to or from the pixel signal wiring 50, and the switching circuit 260(second switching circuit) that electrically couples or uncouples thefirst common wiring 52 to or from the detection electrode wiring 51 andelectrically couples or uncouples the second common wiring 53 to or fromthe detection electrode wiring 51.

In the above-described configuration, the pixel signal Vpix istransmitted to the first common wiring 52 in the display period Pd, andthe detection input/output signal AFE is transmitted to the first commonwiring 52 in the detection period Pt. The display drive signal VCOM istransmitted to the second common wiring 53 in the display period Pd, andthe guard signal Vgd is transmitted to the second common wiring 53 inthe detection period Pt. The switching circuit 220 (first switchingcircuit) applies the pixel signal Vpix to the pixel signal wiring 50 inthe display period Pd, and applies the detection input/output signal AFEor the guard signal Vgd to the detection electrode wiring 51 in thedetection period Pt. The switching circuit 210 (second switchingcircuit) applies the display drive signal VCOM to the detectionelectrode wiring 51 in the display period Pd, and applies the detectioninput/output signal AFE or the guard signal Vgd to the detectionelectrode wiring 51 in the detection period Pt.

The display device 1 d according to the second embodiment can transmit,through the first common wiring 52, both the pixel signal Vpix to besupplied to the pixel Pix and the detection input/output signal AFE tobe supplied to the detection electrode DE. This configuration can reducethe number of lines of the wiring coupled to the display panel 10 d, andcan reduce the width of the peripheral region 18 outside the displayregion 20 and the width of the coupling portion between the displaypanel 10 d and the circuit board 16 c.

The present embodiment can provide the display device 1 d that canreduce the number of lines of the wiring coupled to the display panel 10d.

Third Embodiment

Hereinafter, components having the same functions as those of theabove-described first or second embodiment will be given the samereference numerals as those in the first or second embodiment, and willnot be described below. A display device of a third embodiment will bedescribed mainly in terms of differences from the first embodiment.

FIG. 26 is a block diagram illustrating a configuration example of thedisplay device according to the third embodiment. FIG. 27 is a diagramillustrating a configuration of an output circuit and the couplingcircuit of the display device according to the third embodiment. FIG. 28is a diagram illustrating a timing control example of the display deviceaccording to the third embodiment.

As illustrated in FIG. 27, an output circuit 100 d of a display device 1e according to the third embodiment includes the switching circuit 110and a switching circuit 160. The output circuit 100 d includes, forexample, a multiplexer.

The switching circuit 160 switches between the guard signal Vgd and thedetection input/output signal AFE. The switching circuit 160 includes aswitch SW161 and a switch SW162. In the present embodiment, the guardsignal Vgd or the detection input/output signal AFE selected by theswitching circuit 160 is supplied to the first common wiring 52 in acircuit board 16 d.

The following describes the control states of the respective switches inthe display period Pd of the display device 1 e according to the thirdembodiment.

As illustrated in FIG. 28, in the display period Pd, the switches SW111,SW211, and SW221 are controlled to be on, and the switches SW112, SW161,SW162, and SW212 are controlled to be off. As a result, the pixel signalVpix is applied to the pixel signal wiring 50, and the display drivesignal VCOM is applied to the detection electrode wiring 51.

The following describes the control states of the respective switches inthe detection period Pt of the display device 1 e according to the thirdembodiment.

As illustrated in FIG. 28, in the detection period Pt, the switchesSW112 and SW212, the switches SW161 corresponding to the non-selecteddetection electrodes DE, and the switch SW162 corresponding to theselected detection electrode DE are each controlled to be on, and theswitches SW111 and SW211, the switch SW161 corresponding to the selecteddetection electrode DE, and the switches SW162 corresponding to thenon-selected detection electrodes DE are each controlled to be off. As aresult, the detection input/output signal AFE is applied to a line ofthe detection electrode wiring 51 corresponding to the selecteddetection electrode DE, and the guard signal Vgd is applied to lines ofthe detection electrode wiring 51 corresponding to the non-selecteddetection electrodes DE.

Specifically, in the detection period Pt1(1,4), the switches SW112 andSW212, the switches SW161(1,3), SW161(1,1), and SW161(1,2) correspondingto the non-selected detection electrodes DE(1,3), DE(1,1), and DE(1,2),and the switch SW162(1,4) corresponding to the selected detectionelectrode DE(1,4) are each controlled to be on. In the detection periodPt1(1,4), the switches SW111 and SW211, the switch SW161(1,4)corresponding to the selected detection electrode DE(1,4), and theswitches SW162(1,3), SW162(1,1), and SW162(1,2) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,1), and DE(1,2) are eachcontrolled to be off.

In the detection period Pt1(1,3), the switches SW112 and SW212, theswitches SW161(1,4), SW161(1,1), and SW161(1,2) corresponding to thenon-selected detection electrodes DE(1,4), DE(1,1), and DE(1,2), and theswitch SW162(1,4) corresponding to the selected detection electrodeDE(1,3) are each controlled to be on. In the detection period Pt1(1,3),the switches SW111 and SW211, the switch SW161(1,3) corresponding to theselected detection electrode DE(1,3), and the switches SW162(1,4),SW162(1,1), and SW162(1,2) corresponding to the non-selected detectionelectrodes DE(1,4), DE(1,1), and DE(1,2) are each controlled to be off.

In the detection period Pt2(1,2), the switches SW112 and SW212, theswitches SW161(1,3), SW161(1,4), and SW161(1,1) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,4), and DE(1,1), and theswitch SW162(1,2) corresponding to the selected detection electrodeDE(1,2) are each controlled to be on. In the detection period Pt2(1,2),the switches SW111 and SW211, the switch SW161(1,2) corresponding to theselected detection electrode DE(1,2), and the switches SW162(1,3),SW162(1,4), and SW162(1,1) corresponding to the non-selected detectionelectrodes DE(1,3), DE(1,4), and DE(1,1) are each controlled to be off.

In the detection period Pt2(1,1), the switches SW112 and SW212, theswitches SW161(1,3), SW161(1,4), and SW161(1,2) corresponding to thenon-selected detection electrodes DE(1,3), DE(1,4), and DE(1,2), and theswitch SW162(1,1) corresponding to the selected detection electrodeDE(1,1) are each controlled to be on. In the detection period Pt2(1,1),the switches SW111 and SW211, the switch SW161(1,1) corresponding to theselected detection electrode DE(1,1), and the switches SW162(1,3),SW162(1,4), and SW162(1,2) corresponding to the non-selected detectionelectrodes DE(1,3), DE(1,4), and DE(1,2) are each controlled to be off.

Also in the display device 1 e according to the third embodiment, theconfiguration may be such that the switching circuit 110 is fixed at thedisplay drive signal VCOM, that is, the display drive signal VCOM issupplied to the switching circuit 210 (second switching circuit) even inthe detection period Pt. Alternatively, an aspect may be such that theswitching circuit 110 is not provided, and the display drive signal VCOMis supplied to the second common wiring 53.

In this case, the switch SW161 corresponds to the switch SW132 in thefirst comparative example with respect to the first embodiment, and theswitch SW162 corresponds to the switch SW133 in the first comparativeexample with respect to the first embodiment. In the third embodiment,there is not provided any switch corresponding to the switch SW141 ofthe first comparative example with respect to the first embodiment.Since the present embodiment has the configuration in which thedetection input/output signal AFE or the guard signal Vgd selected bythe switching circuit 160 is applied to the first common wiring 52 inthe detection period Pt, no switch corresponding to the switch SW141 isrequired. Hence, according to a modification of the third embodiment,the output circuit 100 d of the display device 1 e can be replaced withthe output circuit 100 a of the display device 1 a according to thefirst comparative example with respect to the first embodiment. That is,the display device 1 e according to the modification of the thirdembodiment can be configured by using a drive circuit 19 a of thedisplay device 1 a according to the first comparative example withrespect to the first embodiment also as a drive circuit 19 d.

The configuration can be such that the burn-in is prevented fromoccurring in the standby state in which no screen display is made, inthe same way as the configuration according to the modification of thefirst embodiment. Specifically, the configuration further includes theswitching circuit 250 (third switching circuit). The display drivesignal VCOM or the guard signal Vgd selected by the switching circuit110 is supplied to the outer frame wiring 55 provided in the peripheralregion 18, and the switch SW251 is controlled to be on in the detectionperiod Pt. This configuration allows the pixel signal wiring 50 to avoidfrom being in the floating state.

With the configuration of the display device 1 e according to the thirdembodiment, the configuration illustrated in FIG. 27 and the timingcontrol illustrated in FIG. 28 allow both the pixel signal Vpix that issupplied to the pixel Pix and the detection input/output signal AFE thatis supplied to the detection electrode DE to be transmitted through thefirst common wiring 52. Specifically, the pixel signal Vpix is suppliedthrough the first common wiring 52 in the display period Pd, and thedetection input/output signal AFE is supplied through the first commonwiring 52 in the detection period Pt. The pixel signal Vpix is appliedto the pixel signal wiring 50 in the display period Pd, and thedetection input/output signal AFE is applied to the detection electrodewiring 51 in the detection period Pt. This configuration can reduce thenumber of lines of the wiring coupled to the display panel 10, and canreduce the width of the peripheral region 18 outside the display region20 and the width of the coupling portion between the display panel 10and the circuit board 16 d.

As described above, the display device 1 e according to the thirdembodiment includes the display panel 10 provided with the displayregion 20 including the pixels Pix and with the detection electrodes.The display panel 10 includes the lines of the first common wiring 52each of which transmits the pixel signal Vpix to be supplied to thepixel Pix or the detection input/output signal AFE to be supplied to thedetection electrode DE, the pixel signal wiring 50 electrically coupledto the pixels Pix, the detection electrode wiring 51 electricallycoupled to the detection electrodes DE, the switching circuit 220 (firstswitching circuit) that electrically couples or uncouples the firstcommon wiring 52 to or from the pixel signal wiring 50, and theswitching circuit 210 (second switching circuit) that electricallycouples or uncouples the first common wiring 52 to or from the detectionelectrode wiring 51.

In the above-described configuration, the pixel signal Vpix istransmitted to the first common wiring 52 in the display period Pd, andthe detection input/output signal AFE is transmitted to the first commonwiring 52 in the detection period Pt. The switching circuit 220 (firstswitching circuit) applies the pixel signal Vpix to the pixel signalwiring 50 in the display period Pd. The switching circuit 210 (secondswitching circuit) applies the detection input/output signal AFE to thedetection electrode wiring 51 in the detection period Pt.

The display device 1 e according to the third embodiment includes thesecond common wiring 53 that transmits the display drive signal VCOM tobe supplied to the detection electrode DE. The switching circuit 210(second switching circuit) electrically couples or uncouples the secondcommon wiring 53 to or from the detection electrode DE, and applies thedisplay drive signal VCOM to the detection electrode wiring 51 in thedisplay period Pd.

In the above-described configuration, the detection input/output signalAFE or the guard signal Vgd is transmitted to the first common wiring 52in the detection period Pt. The switching circuit 210 (second switchingcircuit) applies the detection input/output signal AFE or the guardsignal Vgd to the detection electrode wiring 51 in the detection periodPt.

The display device 1 e according to the third embodiment can transmit,through the first common wiring 52, both the pixel signal Vpix to besupplied to the pixel Pix and the detection input/output signal AFE tobe supplied to the detection electrode DE. This configuration can reducethe number of lines of the wiring coupled to the display panel 10, andcan reduce the width of the peripheral region 18 outside the displayregion 20 and the width of the coupling portion between the displaypanel 10 and the circuit board 16.

The present embodiment can provide the display device 1 e that canreduce the number of lines of the wiring coupled to the display panel10.

In the above-described embodiments, the examples have been described inwhich the present disclosure is applied to the aspect of detecting theposition of the detection target object on the detection surface of thesensing region 30. However, the present disclosure can be applied to anaspect of detecting a force applied to the sensing region 30 by thedetection target object.

The components of the embodiments described above can be combined asappropriate. Other operational advantages accruing from the aspectsdescribed in the embodiments of the present disclosure that are obviousfrom the description herein, or that are conceivable as appropriate bythose skilled in the art will naturally be understood as accruing fromthe embodiments of the present disclosure.

What is claimed is:
 1. A display device comprising a driver integratedcircuit (IC) and a display panel that is provided with a display regionincluding a plurality of pixels and with a plurality of detectionelectrodes, wherein the display panel comprises: a first common wiringline configured to transmit pixel signals to be supplied to the pixelsand a detection input/output signal to be supplied to a first detectionelectrode that is one of the detection electrodes; a pixel signal wiringline electrically coupled to the pixels; a detection electrode wiringline electrically coupled to the first detection electrode; a firstswitching circuit configured to electrically couple or uncouple thefirst common wiring line to or from the pixel signal wiring line; and asecond switching circuit configured to electrically couple or uncouplethe first common wiring line to or from the detection electrode wiringline, each of the first switch circuit and the second switch circuit isformed on a peripheral region outside of the display region and outsideof the driver IC, the first common wiring line has a configuration inwhich one line branches into two, the first common wiring line leas afirst end, a second end, and a third end, the first end is coupled tothe first switching circuit, the second end is coupled to the secondswitching circuit, and the third end is coupled to the driver IC.
 2. Thedisplay device according to claim 1, wherein the first common wiringline is configured to transmit the pixel signals in a display period,and transmit the detection input/output signal in a detection perioddifferent from the display period, the first switching circuit isconfigured to apply the pixel signals to the pixel signal wiring line inthe display period, and the second switching circuit is configured toapply the detection input/output signal to the detection electrodewiring line in the detection period.
 3. The display device according toclaim 2, further comprising a second common wiring line configured totransmit a display drive signal to be supplied to the first detectionelectrode, wherein one end of the second common wiring line is coupledto the driver IC, another end of the second common wiring line iscoupled to the second switch circuit, the second switching circuit isconfigured to electrically couple or uncouple the second common wiringline to or from the detection electrode wiring line, and apply thedisplay drive signal to the detection electrode wiring line in thedisplay period.
 4. The display device according to claim 3, wherein thefirst common wiring line is configured to transmit the detectioninput/output signal or a guard signal synchronized with the detectioninput/output signal in the detection period, and the second switchingcircuit is configured to apply the detection input/output signal or theguard signal to the detection electrode wiring line in the detectionperiod.
 5. The display device according to claim 4, wherein the secondcommon wiring line is configured to transmit the display drive signal inthe display period, and transmit the guard signal in the detectionperiod.
 6. The display device according to claim 2, further comprising asecond common wiring line configured to transmit a display drive signalto be supplied to the first detection electrode or a guard signalsynchronized with the detection input/output signal, wherein the secondcommon wiring line is configured to transmit the display drive signal inthe display period, and transmit the guard signal in the detectionperiod, and the second switching circuit is configured to electricallycouple or uncouple the second common wiring line to or from thedetection electrode wiring line to apply the display drive signal to thedetection electrode wiring line in the display period and apply thedetection input/output signal or the guard signal to the detectionelectrode wiring line in the detection period.
 7. The display deviceaccording to claim 4, wherein the display panel comprises, in theperipheral region outside the display region, outer frame wiringelectrically coupled to the second common wiring line, and furthercomprises a third switching circuit configured to couple or uncouple theouter frame wiring to or from the pixel signal wiring line, and thethird switching circuit is configured to apply the guard signal to thepixel signal wiring line in the detection period.
 8. The display deviceaccording to claim 5, wherein the display panel comprises, in theperipheral region outside the display region, outer frame wiringelectrically coupled to the second common wiring line, and furthercomprises a third switching circuit configured to couple or uncouple theouter frame wiring to or from the pixel signal wiring line, and thethird switching circuit is configured to apply the guard signal to thepixel signal wiring line in the detection period.
 9. The display deviceaccording to claim 6, wherein the display panel comprises, in theperipheral region outside the display region, outer frame wiringelectrically coupled to the second common wiring line, and furthercomprises a third switching circuit configured to couple or uncouple theouter frame wiring to or from the pixel signal wiring line, and thethird switching circuit is configured to apply the guard signal thepixel signal wiring line in the detection period.